Wood preserving and fireproofing composition



Patented Mar. 30, 1937 WOOD PRESERVING AND FIREPROOFING COMPOSITION Cornelius D. Bell, Jr., Detroit, Mich.

No Drawing. Application May 13, 1935, Serial No. 21 273 1 Claim.

This invention relates to a preservative and more particularly to a preservative of wood and cloth, the preservative of my invention being adapted to render wood and cloth water-proof 5 and fire-proof and, additionally, to render wood termite-proof and to prevent cloth from rotting or disintegrating.

The composition of my invention has the additional desirable property of not staining materials treated therewith, and wood, furthermore, will not shrink, swell or warp after treatment with the composition of my invention, if properly seasoned before being so treated.

From the foregoing enumeration of some of the properties of my preservative, it will readily be appreciated that the same will be valuable for the treatment of lumber in general, and, in particular, for the treatment of such articles as shingles, railroad ties and telephone poles, for example.

It is furthermore suggested that my preservative may be advantageously used to treat wooden containers used to hold plants, inasmuch as the composition is not injurious to plants.

A preservative having the qualities mentioned may be made by making a solution of zinc chloride, iron chloride, boric acid and ammonium phosphate. More particularly, a suitable composition of the character mentionedimay be made by dissolving, in 7 gallons of water, 1 pound of zinc chloride, pound of iron chloride, such as ferric chloride, 1%, pounds of boric acid and 11 pounds of ammonium phosphate.

The material to be treated with the preservative of my invention is immersed in the latter until the material is thoroughly saturated, the latter then being taken out of the preservative and dried. In order to properly treat wood, the latter should be allowed to stand in the solution three days for each inch of thickness of the wood.

In the preservative, the ammonium phosphate, the iron chloride, and the boric acid contribute noninfiammable characteristics. The zinc chloride contributes noninflammable characteristics and also is a poison for termites. The iron chlo- 45 ride in the composition releases gas and prevents flame when the treatedwood becomes heated.

I am aware that certain of the above named ingredients have been used for fire-proofing different materials but to my knowledge all of the ingredients have not hitherto been used in a single compound, which is therefore a new salt, in the proportions specified, for preserving and fire-proofing wood and other materials.

The composition can be used under pressures from 250 pounds per square inch to 80,000 pounds per square inch without disintegration. The purpose of course of using pressure is to economize in time and expense when treating wood and other substances. Pressure facilitates impregnation and will decrease the time of immersion to twenty-four hours or less. No Wood will ever require more than a pressure of 1,000 pounds per square inch.

Impregnation should increase the weight of wood twenty per cent and if the wood has not increased in weight to this extent it is not thoroughly impregnated and the operation should be repeated. When fabrics, textiles and the like are to be treated no pressure of course is required, and usually impregnation is complete within two hours, more or less. The weight of such material should increase fifteen per cent to signify that the impregnation is complete.

Pine, fur, red oak and similar woods being porous require less pressure than compact woods such as mahogany, ebony, white oak, hickory, etc.

In action the composition fills the pores of wood, or the interstices of fabric material with a preservative and non-inflammable composition which seals the pores and the interstices and prevents the escape of entrapped air therefrom.

As previously stated the iron chloride in the product forms a gas when heated and this gas is a fire quencher.

What is claimed is:

A wood preserving and fireproofing composition consisting of 1 lb. of zinc chloride, 1b. of iron chloride, 1% lbs. of boric acid, 11 lbs. of ammonium phosphate, and '7 gallons of water.

CORNELIUS D. BELL, JR. 

